AFAIK this is literally the only time google has laid more than a few thousand off at once
Only if you count a single day. If you count yearly Google has not stopped layoffs of "more than a few thousand" since 2023. And I bet some months get above 1000. The big layoff in 2023 was not actually the first time by the way, that was much earlier (there was a wave of office consolidation in the 2010s). Also the 2023 layoff was at least 3 distinct waves.
And constant layoffs very much have the result on morale you'd expect today.
They did it again in 2024 and then switched to continuous drip of small "layoffs" and encouraging attrition. They have tried various layoff flavors: random, strategic, political, voluntary, and now in their continuous microlayoff era good luck distilling a consistent simple explanation for the day to day decisions of many thousands of managers.
Google has cost-cut their old hiring and performance management processes, and eliminated many perks and benefits that were peculiar to Google. As the unique characteristics of Google as an institution are pared away, it makes sense that they would also adopt the standard approach to layoffs and that is what we have seen since 2023.